US8284374B2 - Liquid crystal display device - Google Patents
Liquid crystal display device Download PDFInfo
- Publication number
- US8284374B2 US8284374B2 US12/005,622 US562207A US8284374B2 US 8284374 B2 US8284374 B2 US 8284374B2 US 562207 A US562207 A US 562207A US 8284374 B2 US8284374 B2 US 8284374B2
- Authority
- US
- United States
- Prior art keywords
- liquid crystal
- dichroic dye
- substrate
- crystal layer
- polarizing film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active, expires
Links
- 239000004973 liquid crystal related substance Substances 0.000 title claims abstract description 110
- 239000000758 substrate Substances 0.000 claims abstract description 79
- 230000005540 biological transmission Effects 0.000 claims abstract description 36
- 150000001875 compounds Chemical class 0.000 claims description 8
- 239000005262 ferroelectric liquid crystals (FLCs) Substances 0.000 claims description 5
- 125000002147 dimethylamino group Chemical group [H]C([H])([H])N(*)C([H])([H])[H] 0.000 claims description 4
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims description 4
- -1 OC9H19 Chemical group 0.000 claims description 3
- YNUSHIPXRLCOCK-UHFFFAOYSA-N 2-nitro-6-phenylaniline Chemical group C1=CC=C([N+]([O-])=O)C(N)=C1C1=CC=CC=C1 YNUSHIPXRLCOCK-UHFFFAOYSA-N 0.000 claims description 2
- QMEQBOSUJUOXMX-UHFFFAOYSA-N 2h-oxadiazine Chemical compound N1OC=CC=N1 QMEQBOSUJUOXMX-UHFFFAOYSA-N 0.000 claims description 2
- RZVHIXYEVGDQDX-UHFFFAOYSA-N 9,10-anthraquinone Chemical compound C1=CC=C2C(=O)C3=CC=CC=C3C(=O)C2=C1 RZVHIXYEVGDQDX-UHFFFAOYSA-N 0.000 claims description 2
- FQPHHLZBTGYWRR-UHFFFAOYSA-N N-[2-(2-phenylethynyl)phenyl]nitramide Chemical compound [O-][N+](=O)Nc1ccccc1C#Cc1ccccc1 FQPHHLZBTGYWRR-UHFFFAOYSA-N 0.000 claims description 2
- DPOPAJRDYZGTIR-UHFFFAOYSA-N Tetrazine Chemical compound C1=CN=NN=N1 DPOPAJRDYZGTIR-UHFFFAOYSA-N 0.000 claims description 2
- PYKYMHQGRFAEBM-UHFFFAOYSA-N anthraquinone Natural products CCC(=O)c1c(O)c2C(=O)C3C(C=CC=C3O)C(=O)c2cc1CC(=O)OC PYKYMHQGRFAEBM-UHFFFAOYSA-N 0.000 claims description 2
- 150000004056 anthraquinones Chemical class 0.000 claims description 2
- 125000001164 benzothiazolyl group Chemical group S1C(=NC2=C1C=CC=C2)* 0.000 claims description 2
- ZLPCVEVCHZENMS-UHFFFAOYSA-N bis[2-(2-phenylethenyl)phenyl]diazene Chemical compound C(=Cc1ccccc1N=Nc1ccccc1C=Cc1ccccc1)c1ccccc1 ZLPCVEVCHZENMS-UHFFFAOYSA-N 0.000 claims description 2
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 claims description 2
- DZVCFNFOPIZQKX-LTHRDKTGSA-M merocyanine Chemical compound [Na+].O=C1N(CCCC)C(=O)N(CCCC)C(=O)C1=C\C=C\C=C/1N(CCCS([O-])(=O)=O)C2=CC=CC=C2O\1 DZVCFNFOPIZQKX-LTHRDKTGSA-M 0.000 claims description 2
- 229920000343 polyazomethine Polymers 0.000 claims description 2
- 239000000975 dye Substances 0.000 description 49
- 239000010408 film Substances 0.000 description 38
- 230000005684 electric field Effects 0.000 description 14
- 230000010355 oscillation Effects 0.000 description 11
- 239000010409 thin film Substances 0.000 description 11
- 230000008901 benefit Effects 0.000 description 5
- 0 [1*]C1=CC=C(NC2=CC=C(O)C3=C2C(=O)C2=CC=CC=C2C3=O)C=C1 Chemical compound [1*]C1=CC=C(NC2=CC=C(O)C3=C2C(=O)C2=CC=CC=C2C3=O)C=C1 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000011159 matrix material Substances 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 230000001678 irradiating effect Effects 0.000 description 3
- LBDBENXNLQAQKL-FOCLMDBBSA-N [H]N(C)C1=CC=C(/N=N/C2=CC=C([N+](=O)[O-])C=C2)C=C1 Chemical compound [H]N(C)C1=CC=C(/N=N/C2=CC=C([N+](=O)[O-])C=C2)C=C1 LBDBENXNLQAQKL-FOCLMDBBSA-N 0.000 description 2
- RLYOERJLGZURGK-UHFFFAOYSA-N [H]N(C)C1=CC=C(C#CC2=CC=C([N+](=O)[O-])C=C2)C=C1 Chemical compound [H]N(C)C1=CC=C(C#CC2=CC=C([N+](=O)[O-])C=C2)C=C1 RLYOERJLGZURGK-UHFFFAOYSA-N 0.000 description 2
- 230000031700 light absorption Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- NWYWRXLKSXYWRE-UHFFFAOYSA-N CC1=CC=C(N=NC2=CC=C(N=NC3=CC=CC=C3)C=C2)C=C1 Chemical compound CC1=CC=C(N=NC2=CC=C(N=NC3=CC=CC=C3)C=C2)C=C1 NWYWRXLKSXYWRE-UHFFFAOYSA-N 0.000 description 1
- IQDOOYRFBZVZJF-UHFFFAOYSA-N CN(C)C1=CC=C(N=NC2=CC=C(N=NC3=CC=CC=C3)C=C2)C=C1 Chemical compound CN(C)C1=CC=C(N=NC2=CC=C(N=NC3=CC=CC=C3)C=C2)C=C1 IQDOOYRFBZVZJF-UHFFFAOYSA-N 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 238000002835 absorbance Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- YVTHLONGBIQYBO-UHFFFAOYSA-N zinc indium(3+) oxygen(2-) Chemical compound [O--].[Zn++].[In+3] YVTHLONGBIQYBO-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1343—Electrodes
- G02F1/134309—Electrodes characterised by their geometrical arrangement
- G02F1/134363—Electrodes characterised by their geometrical arrangement for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/13725—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on guest-host interaction
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/141—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent using ferroelectric liquid crystals
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1343—Electrodes
- G02F1/134309—Electrodes characterised by their geometrical arrangement
- G02F1/134372—Electrodes characterised by their geometrical arrangement for fringe field switching [FFS] where the common electrode is not patterned
Definitions
- the present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device which improved display grade through an improvement in contrast ratio.
- LCDs liquid crystal display devices
- OLEDs organic light emitting diodes
- PDPs plasma panel display devices
- SEDs surface-conduction electron-emitter display devices
- LCDs liquid crystal display devices
- LCDs which are used in a variety of applications from a display screen of a mobile phone to a TV screen, are one of the most typical flat display devices.
- an LCD includes a liquid crystal display panel for displaying images by receiving video and scan signals from outside and a backlight unit for irradiating light.
- the liquid crystal display device includes a liquid crystal layer disposed between a pair of transparent substrates, and may further include a polarizing film equipped on the pair of substrates, respectively.
- the LCD is not a light-emitting display device which displays images by self-emitting light, rather it is a non-light-emitting display device which displays images by having light supplied from a backlight unit and controlling the transmittance of the supplied light.
- the contrast ratio is generally measured by dividing a white luminance by a black luminance, and particularly, reducing the black luminance is an important factor for improving the contrast ratio.
- contrast ratio decreases, the contrast ratio of a white screen and a black screen decreases, thereby having difficulty in displaying vivid images.
- the present invention is directed to a liquid crystal display device that substantially obviates one or more problems due to limitations and disadvantages of the related art.
- An advantage of the present invention is to provide a liquid crystal display device capable of improving a contrast ratio.
- a liquid crystal display device includes a first substrate including a first alignment film and a first polarizing film having a first transmission axis parallel to an alignment direction of the first alignment film, a second substrate including a second alignment film and a second polarizing film having a second transmission axis perpendicular to the first transmission axis of the first polarizing, and a liquid crystal layer between the first and second substrates, the liquid crystal layer including dichroic dye, wherein the liquid crystal is aligned in a horizontal direction.
- FIG. 1 is a perspective view for illustrating optical properties of a dichroic dye
- FIG. 2 is a sectional view for illustrating an arrangement relationship between dichroic dye molecules and liquid crystal molecules
- FIG. 3 is a perspective view illustrating the constitution of a liquid crystal display device according to a first embodiment of the present invention
- FIG. 4 is a sectional view illustrating an OFF-state of a liquid crystal display device according to a first embodiment of the present invention
- FIG. 5 is a sectional view illustrating an ON-state of a liquid crystal display device according to a first embodiment of the present invention
- FIG. 6 is a perspective view illustrating an OFF-state of a liquid crystal display device according to a second embodiment of the present invention.
- FIGS. 7A and 7B are perspective views illustrating an ON-state of a liquid crystal display device according to a second embodiment of the present invention.
- the present invention is directed to a liquid crystal display device including a first substrate including a first alignment film and a first polarizing film having a first transmission axis parallel to a alignment direction of the first alignment film; a second substrate including a second alignment film and a second polarizing film having a second transmission axis perpendicular to the first transmission axis of the first polarizing; and a liquid crystal layer between the first and second substrates, the liquid crystal layer including dichroic dye, wherein the liquid crystal is aligned in horizontal direction.
- the present invention also relates to a fringe field switching liquid crystal display panel.
- the dichroic dye is characterized by absorbing light that oscillates in the parallel direction and transmitting light that oscillates in the perpendicular direction with respect to any one axis of a long axis and a short axis of the dichroic dye molecules.
- the dichroic dye is included in a small amount in the liquid crystal layer including liquid crystal molecules which are uniformly aligned in the horizontal direction. At this time, as shown in FIG. 2 , the dichroic dye 134 is aligned parallel to the liquid crystal molecules 132 by a guest-host effect.
- the liquid crystal display device arranged the transmission axis of the polarizing film in the side of light incident and the substrate in the side of light incident such that they are parallel to each other, as well as added the dichroic dye to the liquid crystal layer.
- the linearly polarized light which is transmitted through the polarizing film without application of a voltage, is absorbed to the dichroic dye so as to reduce black luminance and improve the contrast ratio, thereby displaying vivid image.
- dichroic dye used in the liquid crystal display device include any one of an azo-based, azo-stilbene-based, benzothiazolyl polyazomethine-based, azomethine-based, merocyanine-based, methine-arylidene-based, tetrazine-based, oxadiazine-based, carbarzole-azo-based, amino-based or anthraquinon-based dichroic dye, but it is not limited thereto.
- azo-based dichroic dye use can be made of an azo-based compound represented by the following formula 1.
- anthraquinone-based dichroic dye use can be made of a compound represented by the following formula 2 or formula 3.
- R1 is any one group from C 4 H 9 , OC 9 H 19 , or N(CH 3 ) 2 .
- R2 is any one group from C 2 H 5 , C 4 H 9 , OC 5 H 11 , N(CH 3 ) 2 , or CH(CH 3 ) 2 .
- amino-based dichroic dye use can be made of a nitro-amino-biphenyl-based compound represented by the following formula 4 or a nitro-amino tolane-based compound represented by the following formula 5.
- n is a natural number
- n is a natural number
- the present invention is not limited to the dichroic dyes exemplified in the above, and any type of a dichroic dye may be used as long as the dichroic dye absorbs light selectively depending on an oscillation direction of the light.
- a degree of light absorption by the above-mentioned dichroic dye is shown as in the following equation 1 and equation 2.
- a ⁇ ⁇ ⁇ cd [Equation 1]
- a ⁇ ⁇ ⁇ cd [Equation 2]
- a ⁇ and A ⁇ are respectively an absorbance of the short axis and the long axis in the dichroic dye molecules
- ⁇ ⁇ and ⁇ ⁇ are respectively an absorption coefficient of the short axis and the long axis in the dichroic dye molecules
- c is a concentration of the dichroic dye
- d is a cell gap.
- the degree of light absorption increases with increase in the concentration of the dichroic dye, thereby reducing the luminance.
- expressing a gray scale, i.e., gradation becomes difficult.
- the addition ratio of the dichroic dye molecules may be determined, in consideration of the contrast ratio, luminance, or the like, depending on the type and cell gap of the liquid crystal to be used.
- the dichroic dye molecules may be added in an amount of, preferably 10% by weight or less, and more preferably 1% by weight or less.
- the liquid crystal display device may display a black screen without applying a voltage.
- FIG. 3 is a perspective view illustration the constitution of the liquid crystal display device according to a first embodiment of the present invention.
- the same reference numerals refer to the same members.
- the liquid crystal display device is an in-plane switching mode liquid crystal display device including a first substrate 110 a equipped with a first polarizing film 120 a having a transmission axis D in a first direction and the first substrate 110 a having an orientation E parallel to the first direction, a second substrate 110 b equipped with a second polarizing film 120 b having a transmission axis F perpendicular to the transmission axis in the first direction and the second substrate 110 b having an orientation G parallel to the first direction, a liquid crystal layer 130 including a dichroic dye 134 disposed between the first substrate 110 a and the second substrate 110 b , and a backlight unit (not shown) for irradiating light from underneath the first substrate.
- a respective substrate and polarizing film have been illustrated to be separated from each other for the convenience of the description.
- the respective substrate may be equipped with the respective polarizing film by attaching it.
- a transparent plastic substrate made of any one from a glass substrate or PET (polyethylen terephthalate), polyimide, or an epoxy resin is used.
- the first substrate 110 a and the second substrate 110 b may be a thin film transistor array substrate and a color filter substrate, respectively.
- the thin film transistor array substrate includes a plurality of gate lines, a plurality of data lines intersecting the gate lines to define a pixel region, a thin film transistor formed on the intersection region of the gate line and the data line, and a pixel electrode connected with the thin film transistor.
- the thin film transistor array substrate further includes a common electrode formed parallel to the pixel electrode to generate a horizontal electric field for realizing an in-plane switching mode.
- the color filter substrate (not shown) includes a black matrix formed to define a pixel region that corresponds with the pixel region in the thin film transistor array region, and a color filter formed in the pixel region.
- the color filter substrate may further include an overcoat layer formed on the overall surface of the substrate including the black matrix and the color filter.
- the first substrate and the second substrate are arranged so as to have their orientations parallel to each other, and the liquid crystal layer to be disposed between the substrate pair is uniformly aligned in the horizontal direction.
- an alignment layer is formed on the first substrate and the second substrate, and the alignment treatment can be performed by rubbing or photo aligning the alignment layer.
- the first polarizing film is placed to have a transmission axis parallel to the orientation of the first substrate, while the second polarizing film is placed to have a transmission axis perpendicular to the transmission axis of the first polarizing film.
- the liquid crystal layer 130 includes liquid crystal molecules driven by an electric field generated between the pixel electrode and the common electrode on the plane parallel to the substrate.
- the liquid crystal layer 130 contains a dichroic dye 134 .
- the dichroic dye 134 selectively absorbs only the light that oscillates parallel to the long axes in the dye molecules.
- the addition ratio of the dichroic dye 134 is determined, in consideration of the contrast ratio, luminance, or the like, depending on a liquid crystal to be used.
- FIGS. 4 and 5 are sectional views respectively illustrating an OFF-state, without application of a voltage, and an ON-state, with application of a voltage, in the liquid crystal display device according to the first embodiment of the present invention.
- light is irradiated from a backlight 140 positioned underneath the first substrate 110 a in the OFF-state without application of a voltage.
- the light When the irradiated light transmits the first polarizing film 120 a , the light is linearly polarized so as to transmit only the light that oscillates parallel to the transmission axis of the first polarizing film 120 a.
- the first substrate 110 a and the second substrate 110 b are arranged to have the orientation parallel to the transmission axis of the first polarizing film 120 a .
- the linearly polarized light is passed through the liquid crystal layer 130 without changing the oscillation direction.
- the light passed through the second substrate 110 b without the change of the oscillation direction cannot pass through the second polarizing film 120 b placed to have a transmission axis perpendicular to the transmission axis of the first substrate, thereby displaying a black screen.
- the liquid crystal layer 130 contains the dichroic dye 134 in addition to the liquid crystal molecules 132 , and the dichroic dye 134 is aligned parallel to the liquid crystal molecules.
- the long axes of the dichroic dye 134 molecules are aligned parallel to the oscillation direction of the linearly polarized light.
- a part of the linearly polarized light is absorbed by the dichroic dye so as to reduce the black luminance even more.
- the light being linearly polarized by transmitting through the first polarizing film 120 a passes through the liquid crystal layer 130 where the oscillation direction of the light rotates 90° from the oscillation direction of the linearly polarized light.
- the light whose oscillation direction rotated 90° can pass through the second polarizing film 120 b having the transmission axis perpendicular to the transmission axis of the first polarizing film 120 a , thereby displaying a white screen.
- the dichroic dye 134 included in the liquid crystal layer 130 is aligned parallel to the liquid crystal molecules, that is, parallel to the applied electric field.
- the orientation of the dichroic dye 134 also changes such that the long axes of the dichroic dye 134 molecules align perpendicular to the oscillation direction of the light passing through the liquid crystal layer 130 .
- the light oscillating perpendicular to the long axes of the dichroic dye 134 molecules is barely absorbed by the dichroic dye 134 , thereby displaying a white screen, and at the same time, minimizing the reduction of luminance by the dichroic dye 134 .
- liquid crystal display device described the in-plane switching mode liquid crystal display device.
- the device may be applied in the same manner for a fringe field switching mode liquid crystal display device.
- FIG. 6 is a perspective view illustrating the case without application of a voltage in the liquid crystal display device according to the second embodiment of the present invention.
- the liquid crystal display device is a ferroelectric liquid crystal display device including a first substrate 110 a equipped with a first polarizing film 120 a having a transmission axis I in a first direction, the first substrate 110 a having an orientation parallel to the first direction I, a second substrate 110 b equipped with a second polarizing film 120 b having a transmission axis II perpendicular to the transmission axis I in the first direction, the second substrate 120 b having an orientation parallel to the first direction, a liquid crystal layer 130 disposed between the first substrate 110 a and the second substrate 110 b , and a backlight unit (not shown) for irradiating light from underneath the first substrate 110 a .
- the liquid crystal layer 130 is formed of a ferroelectric liquid crystal including smetic liquid crystal molecules 132 , and contains a dichroic dye 134 .
- the first substrate 110 a and the second substrate 110 b include a thin film transistor array substrate and a color filter substrate, respectively.
- the thin film transistor array substrate includes a plurality of gate lines, a plurality of data lines intersecting the gate lines to define a pixel region, a thin film transistor formed on the intersection region of the gate line and the data line, and a pixel electrode connected with the thin film transistor.
- the color filter substrate includes a black matrix formed to define a pixel region that corresponds with the pixel region in the thin film transistor array region, a color filter formed in the pixel region, and a common electrode formed on the overall surface of a substrate including the black matrix and color filter.
- the common electrode is made of a transparent conductive substance, for example, indium-tin-oxide (ITO) or indium-zinc-oxide (IZO).
- ITO indium-tin-oxide
- IZO indium-zinc-oxide
- the ferroelectric liquid crystal is driven by a perpendicular electric field in the liquid crystal display device according to the second embodiment of the present invention.
- the first substrate and the second substrate are arranged so as to have their orientations parallel to each other, and the liquid crystal layer to be disposed between the substrate pair is uniformly aligned in the horizontal direction.
- FIGS. 7A and 7B are perspective views illustrating the case with application of a voltage.
- the linearly polarized light passes through the liquid crystal layer without the change in its oscillation direction.
- the light transmitted the second substrate 110 b without the change in the oscillation direction cannot pass through the second polarizing film 120 b placed to have the transmission axis perpendicular to the transmission axis of the first substrate, thereby displaying a black screen.
- the liquid crystal layer as shown in FIG. 6 , has rod-shaped smetic liquid crystal molecules 132 .
- the liquid crystal molecules have orientational order as well as the positional order at the same time.
- the liquid crystal has a plurality of layers in which a director of the liquid crystal molecules is arranged to be tilted with a certain angle with respect to the substrate.
- the long axes of the liquid crystal molecules in each layer are aligned parallel to the transmission axis II of the first polarizing film when seen from the direction of the incident light.
- the dichroic dye 134 included in the liquid crystal layer is aligned parallel to the liquid crystal molecules 132 by a guest-host effect.
- the dichroic dye 134 provides an effect of reducing black luminance even more in the black screen by absorbing a part of the light that passes through the liquid crystal layer.
- the long axes of the dichroic dye molecules aligned parallel to the liquid crystal and the oscillation direction of the linearly polarized light are parallel to each other such that the linearly polarized light is absorbed to the dichroic dye molecules, thereby reducing black luminance.
- FIG. 7A illustrates the case of applying a voltage of positive polarity to the common electrode and applying a voltage of negative polarity to the pixel electrode.
- FIG. 7B illustrates the case of applying a voltage of positive polarity to the pixel electrode and applying a voltage of negative polarity to the common electrode.
- the liquid crystal molecules perform cone motion, as shown in FIGS. 7A and 7B , in which each molecule rotates along the imaginary cylinder surface with one end of the long axis of the liquid crystal molecule fixated.
- the rotational direction of the cone motion is determined by the direction of an electric field.
- the long axes of the liquid crystal molecules are aligned parallel to the transmission axis I of the first polarizing film 120 a when seen from the screen direction.
- the linearly polarized light passed through the first polarizing film becomes elliptically polarized light by passing through the liquid crystal layer.
- the direction of the elliptically polarized light is determined by a phase difference caused by a cell gap, or the like.
- the elliptically polarized light passed through the liquid crystal layer transmits only the light parallel to the transmission axis of the second polarizing film, thereby displaying a white screen.
- the liquid crystal display device included the dichroic dye in the ferroelectric liquid crystal to have effects capable of displaying vivid images having a high contrast ratio by reducing black luminance of the black screen in addition to realizing the liquid crystal display device with a high response rate.
- the liquid crystal display device has the first and the second polarizing film arranged such that the respective transmission axes are perpendicular to each other, without any additional process.
Abstract
Description
A⊥=α⊥cd [Equation 1]
A∥=α∥cd [Equation 2]
Claims (12)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR10-2007-0048409 | 2007-05-18 | ||
KR1020070048409A KR101286529B1 (en) | 2007-05-18 | 2007-05-18 | Liquid Crystal Display Device |
Publications (2)
Publication Number | Publication Date |
---|---|
US20080284972A1 US20080284972A1 (en) | 2008-11-20 |
US8284374B2 true US8284374B2 (en) | 2012-10-09 |
Family
ID=40027135
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/005,622 Active 2030-09-20 US8284374B2 (en) | 2007-05-18 | 2007-12-28 | Liquid crystal display device |
Country Status (4)
Country | Link |
---|---|
US (1) | US8284374B2 (en) |
KR (1) | KR101286529B1 (en) |
CN (1) | CN101308279B (en) |
TW (1) | TWI365329B (en) |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101683269B1 (en) * | 2009-11-23 | 2016-12-06 | 삼성전자 주식회사 | Liquid crystal display and method of manufacturing the same |
CN101923253B (en) * | 2010-07-29 | 2012-07-11 | 昆山龙腾光电有限公司 | Liquid crystal display panel and liquid crystal display device |
TWI471648B (en) * | 2012-03-29 | 2015-02-01 | Chunghwa Picture Tubes Ltd | Transparent liquid crystal display device and manufacturing method for the same |
CN102608796B (en) * | 2012-04-01 | 2015-05-13 | 福建华映显示科技有限公司 | Transparent liquid crystal display device and manufacturing method thereof |
CN105572957B (en) * | 2013-01-05 | 2020-01-31 | 京东方科技集团股份有限公司 | Control method of display devices and display system |
CN103323968B (en) * | 2013-05-28 | 2015-11-25 | 京东方科技集团股份有限公司 | A kind of display base plate and preparation method thereof, display device |
CN105392865A (en) * | 2013-06-14 | 2016-03-09 | 华东理工大学 | Dichroic-dye-doped isotropic chiral liquid crystals |
CN104503167A (en) * | 2014-12-31 | 2015-04-08 | 深圳市华星光电技术有限公司 | Liquid crystal display |
JP2017090543A (en) * | 2015-11-04 | 2017-05-25 | 株式会社ポラテクノ | Liquid crystal display |
WO2018097673A1 (en) * | 2016-11-25 | 2018-05-31 | 주식회사 엘지화학 | Liquid crystal film cell and use thereof |
KR101941118B1 (en) * | 2016-11-25 | 2019-01-23 | 주식회사 엘지화학 | Liquid crystal cell and use thereof |
KR102028446B1 (en) * | 2017-10-17 | 2019-10-04 | 주식회사 큐시스 | Smart window for controlling visible light and infrared |
CN110456581A (en) * | 2018-05-07 | 2019-11-15 | 青岛海信电器股份有限公司 | A kind of display panel and display equipment |
CN109521597A (en) * | 2018-11-14 | 2019-03-26 | 惠州市华星光电技术有限公司 | It is always on type vertical alignment liquid crystal display panel |
CN112987379A (en) * | 2019-12-12 | 2021-06-18 | 京东方科技集团股份有限公司 | Light-adjusting glass and glass module |
CN114063362B (en) * | 2021-11-16 | 2023-04-07 | 电子科技大学 | Two-dimensional liquid crystal laser deflector |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58113286A (en) | 1981-12-28 | 1983-07-06 | Alps Electric Co Ltd | Color liquid crystal display element |
JPS63257723A (en) | 1987-04-16 | 1988-10-25 | Asahi Glass Co Ltd | Liquid crystal display device |
US5046823A (en) * | 1988-03-24 | 1991-09-10 | Nippondenso Co., Ltd. | Ferroelectric liquid crystal electro-optic apparatus and manufacturing method thereof |
EP0520754A2 (en) | 1991-06-24 | 1992-12-30 | Kabushiki Kaisha Toshiba | Liquid crystal display element |
US5347378A (en) * | 1991-04-04 | 1994-09-13 | Displaytech, Inc. | Fast switching color filters for frame-sequential video using ferroelectric liquid crystal color-selective filters |
US20060001809A1 (en) | 2004-06-30 | 2006-01-05 | Lg Philips Lcd Co., Ltd. | Liquid crystal display device and method for fabricating the same |
US20060146249A1 (en) | 2004-12-30 | 2006-07-06 | Lg.Philips Lcd Co., Ltd. | In-plane switching mode liquid crystal display device and fabrication method thereof |
TW200632005A (en) | 2005-01-21 | 2006-09-16 | Fuji Photo Film Co Ltd | Polymer film, optically-compensatory film, process for producing the same, polarizing plate and liquid-crystal display device |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1067987A (en) * | 1988-03-24 | 1998-03-10 | Denso Corp | Liquid crystal electrooptical device |
CN1213327C (en) * | 1998-03-19 | 2005-08-03 | 松下电器产业株式会社 | Resin-liquid crystal formed body, liquid crystal device, liquid crystal display comprising the same and methods of manufacturing the same |
JP5138136B2 (en) * | 2001-07-30 | 2013-02-06 | 駿介 小林 | Liquid crystal display element |
TWI262375B (en) * | 2004-07-22 | 2006-09-21 | Aopen Inc | Assembling device without the use of tool and host computer case adopting the same |
-
2007
- 2007-05-18 KR KR1020070048409A patent/KR101286529B1/en active IP Right Grant
- 2007-12-26 TW TW096150391A patent/TWI365329B/en not_active IP Right Cessation
- 2007-12-28 CN CN2007103063549A patent/CN101308279B/en not_active Expired - Fee Related
- 2007-12-28 US US12/005,622 patent/US8284374B2/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58113286A (en) | 1981-12-28 | 1983-07-06 | Alps Electric Co Ltd | Color liquid crystal display element |
JPS63257723A (en) | 1987-04-16 | 1988-10-25 | Asahi Glass Co Ltd | Liquid crystal display device |
US5046823A (en) * | 1988-03-24 | 1991-09-10 | Nippondenso Co., Ltd. | Ferroelectric liquid crystal electro-optic apparatus and manufacturing method thereof |
US5347378A (en) * | 1991-04-04 | 1994-09-13 | Displaytech, Inc. | Fast switching color filters for frame-sequential video using ferroelectric liquid crystal color-selective filters |
EP0520754A2 (en) | 1991-06-24 | 1992-12-30 | Kabushiki Kaisha Toshiba | Liquid crystal display element |
US20060001809A1 (en) | 2004-06-30 | 2006-01-05 | Lg Philips Lcd Co., Ltd. | Liquid crystal display device and method for fabricating the same |
US20060146249A1 (en) | 2004-12-30 | 2006-07-06 | Lg.Philips Lcd Co., Ltd. | In-plane switching mode liquid crystal display device and fabrication method thereof |
TW200632005A (en) | 2005-01-21 | 2006-09-16 | Fuji Photo Film Co Ltd | Polymer film, optically-compensatory film, process for producing the same, polarizing plate and liquid-crystal display device |
Also Published As
Publication number | Publication date |
---|---|
US20080284972A1 (en) | 2008-11-20 |
CN101308279B (en) | 2012-07-18 |
TWI365329B (en) | 2012-06-01 |
KR101286529B1 (en) | 2013-07-17 |
TW200846771A (en) | 2008-12-01 |
CN101308279A (en) | 2008-11-19 |
KR20080102072A (en) | 2008-11-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8284374B2 (en) | Liquid crystal display device | |
US8164720B2 (en) | Liquid crystal display apparatus | |
US7616283B2 (en) | In-plane switching mode LCD device | |
US8294852B2 (en) | Liquid crystal display device comprising a combination of O-type polarizers and E-type polarizers | |
TWI390306B (en) | Transparent liquid crystal display device | |
US9261740B2 (en) | Liquid crystal panel | |
US11450290B2 (en) | Pixel structure, display panel and display device | |
US9690139B2 (en) | Display panel | |
US8045115B2 (en) | Liquid crystal display with different twisting directions of liquid crystal molecules | |
US7420640B2 (en) | In-plane switching mode liquid crystal device and method for manufacturing the same | |
US7394512B2 (en) | Liquid crystal display device | |
US9448438B2 (en) | Liquid crystal display panel comprising alignment molecules having a core portion, a polarity portion, and a tail portion | |
US7382427B2 (en) | Liquid crystal display device | |
US20090073372A1 (en) | Liquid crystal display device and liquid crystal display | |
US20130148066A1 (en) | Liquid crystal panel and liquid crystal display device | |
US20080151149A1 (en) | Liquid crystal display | |
US10545369B2 (en) | Display device | |
KR20170063298A (en) | Liquid crystal display device | |
US7889299B2 (en) | Liquid crystal display device and method of fabricating the same | |
WO2018020724A1 (en) | Liquid crystal display device | |
US8497946B2 (en) | Liquid crystal display device | |
JP2006208531A (en) | Liquid crystal display device | |
Jo et al. | 60‐3: High Contrast In‐plane Switching (IPS) Mode using Dichroic‐dye Liquid Crystal | |
KR20170063299A (en) | Liquid crystal display device | |
JP3795178B2 (en) | Liquid crystal display |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: LG.PHILIPS LCD CO., LTD., KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KIM, KYEONG JIN;BAIK, IN SU;REEL/FRAME:020337/0856 Effective date: 20071226 |
|
AS | Assignment |
Owner name: LG DISPLAY CO., LTD., KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LG. PHILIPS LCD CO., LTD.;REEL/FRAME:021787/0339 Effective date: 20080304 Owner name: LG DISPLAY CO., LTD.,KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LG. PHILIPS LCD CO., LTD.;REEL/FRAME:021787/0339 Effective date: 20080304 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 12TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1553); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 12 |